The rising world population is placing increasing demands on the supply of foods, especially those that are a source of protein. The production and consumption of meat as a protein source is also becoming increasingly unsustainable. The high price of meat means that its availability in many parts of the world is limited, if not non-existent in some areas. Most of the world's less expensive protein sources originate from a variety of pulses, grains and lentils. These sources usually have a high concentration of protein, but also have some drawbacks in respect of digestibility and anti-nutritional factors. Moreover, for many people, these cheaper protein sources do not have a very pleasant taste or texture compared with meat products.
There has been an ongoing search for solutions to the above problems by providing affordable high protein alternatives to meat products, especially for developing or emerging market countries.
Beans of different varieties are a well-known source of protein. Beans are commonly prepared by soaking in water overnight and then cooking. It is also well-known to treat the cooked beans with a fungus which enables this highly proteinaceous material to be formed into a cake. This process is known to many as the tempeh process. The tempeh process increases digestibility of the raw material by 5 to 10%.
Tempeh (also spelled tempe) is an Indonesian foodstuff based on beans (normally soybeans), which has a tradition dating back many centuries in Java. Its popularity is increasing in various regions including Japan, the USA, and Western Europe. It is made by a natural fermentation process involving a Rhizopus fungus plus many different bacteria and yeasts. The process binds the beans into a cake form, similar to a firm vegetarian burger patty. In contrast to tofu, which is derived from soybeans, tempeh is a whole bean product having different nutritional characteristics and textural qualities. The tempeh fermentation process, and its retention of the whole bean, means that the product has a higher content of protein, dietary fibre, and vitamins. In particular, the fermentation process improves some characteristics of soybeans including protein level (up to 40% of the dry mass), fatty acid composition (Hering, L., et al., Lipid/Fett, 1991, 93(8), 303-308), the level and pattern of oligosaccharides (Rehms, H. and Barz, W., Appl. Microbiol. Biotechnol., 1995, 44, 47-52), and the amount of several vitamins, especially vitamin B12 and vitamin D (Keuth, S. and Bisping, B., J. Appl. Bacteriol., 1993, 75, 427-434; Denter, J., et al., J. Food Mycol., 1998, 1, 149-161). The product is normally consumed in the form of slices that have been fried, as a type of Indonesian satay, as a peppered paste (sambal), or as vegetarian tempeh burger.
The problems with using soybeans as a source of proteins for preparing meat alternative (or replacer) products using a tempeh process relate to both texture and taste. The use of whole soybeans gives neither a texture nor a taste similar to minced meat. The whole beans remain visible in the product, can be felt in the mouth when chewing, and also give a nutty soya flavour. While digestibility is increased compared to regular cooking of beans, a large portion of the soya bean still remains indigestible by the human body.
In the search for new sources of protein that may be subjected to a fermentation process similar to the tempeh process, the focus has been on protein sources, such as beans, that can provide a rich source of nutrients to a fungus. Thus, most beans are a good source of carbohydrates, fatty acids, vitamins and minerals, as well as protein. Sources that are high in protein, but limited in other materials, have previously been considered to be unsuitable for supporting the growth of a fungus in a tempeh fermentation. Gluten from sources such as wheat, barley, rice, and rye contain protein and small amounts of starch, but not much more. Gluten has therefore not previously been considered as a protein source in the tempeh process.
However, the applicant has now found that gluten, especially wheat gluten, as an affordable protein source, can be processed using the principles of tempeh fermentation to produce a new meat alternative.
The object of the present invention is therefore to provide a vegetarian minced meat replacer which has similar taste and texture attributes compared to minced meat or at least to provide a useful alternative to existing meat replacers.